The overall objectives of this project are to study changes in cell surface glycosphingolipids and sialidase and sialyltransferase activities after cell transformation. Neuroblastoma, oligodendroglioma, and astrocytoma cells are the transformed cells which will be studied. The results obtained will be compared with those for neurons, oligodendroglia, and astrocytes. The neuroblastoma exemplifies a malignant neoplasm, the oligodendroglioma and astrocytomas, benign neoplasms.